RT Journal Article
T1 Semi-automated computational investigation of the oxidative degradation mechanisms of bisphenol A in Fenton-type processes
A1 Chacón Morales, Pablo A.
A1 Fernández Ramos, Antonio
A1 González-Rodríguez, Jorge
A1 Moreira Vilar, María Teresa
A1 Martínez Núñez, Emilio
A1 Ferro Costas, David
K1 BPA oxidative degradation
K1 Autonomous reaction mechanism discovery
K1 Kinetic modeling
K1 AutoMeKin
K1 Pilgrim
AB Bisphenol A (BPA) is a widespread industrial contaminant and endocrine disruptor whose efficient removal remains challenging because multiple, competing radical channels operate under Fenton-type advanced oxidation conditions. Here, we present a semi-automated first-principles approach to elucidate this process, comprising: (i) exhaustive discovery of unimolecular radical transformations with AutoMeKin; (ii) targeted manual construction of initial •OH addition and hydrogen-abstraction transition states; (iii) DFT refinement at ωB97XD/def2-TZVPP with SMD solvation model; (iv) selective microsolvation (up to two water molecules) for high potential energy barriers; (v) transition state theory rate constants evaluation for all elementary steps, and unified statistical treatment of dual bottlenecks for bimolecular •OH reactions; and (vi) Kinetic Monte Carlo (KMC) simulations with Pilgrim to obtain product distributions. The reaction network maps all feasible early •OH additions (ipso/ortho/meta/para), phenolic O–H abstraction, multistep hydroxylations, attempted dehydration steps, epoxidation, ring opening, and C–C scission leading to hydroxylated, quinonoid, lactone, and cleavage products. Selective microsolvation lowers critical rearrangement barriers, converting otherwise rate-determining steps into kinetically viable channels. KMC analysis identifies a characteristic ≈2:1 [•OH]:[BPA] threshold. Below it, early hydroxylated and ketone intermediates persist (e.g., catecholic and cyclohexadienone forms), whereas above it they are rapidly converted into trihydroxylated derivatives, ring-cleavage fragments, and quinone products. A reduced mechanism derived from sensitivity analysis reproduces the kinetics of the full network while retaining only essential OH-addition and phenolic H-abstraction steps. This integrated workflow thus provides mechanistic insight and a predictive, computationally efficient kinetic model readily transferable to other organic contaminants in advanced oxidation processes.
PB Elsevier
SN 1873-3212
YR 2025
FD 2025-10-06
LK https://hdl.handle.net/10347/43289
UL https://hdl.handle.net/10347/43289
LA eng
NO Chemical Engineering Journal 524 (2025) 169248
NO M.T.M. acknowledges support from the CIES project (PID2022-142334OB-I00), funded by MICIU/AEI/10.13039/501100011033 and FEDER, EU. A.F.-R., E.M.-N. and M.T.M. acknowledge support from the SPOTLIGHT project (PDC2021-121540-I00), funded by MICIU/AEI/10.13039/501100011033 and the European Union NextGenerationEU/PRTR. A.F.-R., D.F.-C., E.M.-N., and J.G.-R. acknowledge financial support from the Consellería de Educación, Ciencia, Universidades e Formación Profesional (Xunta de Galicia): A.F.-R., D.F.-C. and E.M.-N through the Grupo de referencia competitiva grant (ED431C 2025/06); A.F.-R. through the Centro singular de Investigación de Galicia accreditation 2023-2027 (ED431G 2023/03), co-funded by the European Regional Development Fund (ERDF); and J.G.-R. through his postdoctoral fellowship (ED481B-2025/070). We also thank the Galician Supercomputer Center (CESGA) for providing access to their computational resources.
DS Minerva
RD 24 abr 2026